Farming systems research for crop diversification in Cambodia and Australia

• Cambodia Agricultural Research and Development Institute, Cambodia

Rice is the staple crop in Cambodia, with little else grown. More than 90 per cent of agricultural cropping land is sown to rice. Crop diversification is minimal, even in upland agro-ecological systems that do not suit rice. Government policy is designed to encourage diversification with CARDI taking a lead in placing emphasis on diversified cropping. There are, however, still substantial barriers to diversification. The main is a lack of familiarity with upland crops. This includes extension workers and researchers as well as farmers, whose knowledge of non-rice crops is limited, creating a perception of higher risk for planting non-rice crops. A wet monsoonal season does not guarantee predictable rainfall, this unpredictability adding to the perception of risk. As a result market infrastructure for non-rice crops is lacking.
Crop diversification is also an issue at the centre of a policy thrust from NSW Agriculture, which seeks to hasten change from cereal crops production in parts of the state. The adoption of more sustainable tillage practices was a central theme of this thrust.

The overall objective was to help reduce poverty and contribute to food security at household and national levels through the development of techniques and opportunities for the production of non-rice upland crops in Cambodia. In Australia the focus was on overcoming the constraints to crop diversification and adoption of sustainable practice in broadacre cropping enterprises in the subtropical slopes and plains agro-ecological region of northern Australia.

In Cambodia the project focused on provinces with the potential for expansion of upland rice crops. The research process involved discussion with farmers, validation of local knowledge, documentation of case studies and agronomic field experiments (Cambodia). Problems and research questions were identified in partnership with farmer and community groups in Cambodia with support from the Department of Agricultural Extension through links with the AusAID-funded Cambodia-Australia Agricultural Extension Project. Farmers' attitudes to the focus crops (soybean, mungbean, peanut, cowpea, maize and sesame) were surveyed and benchmarked at commencement of the project with the intention of monitoring fields of a range of crops each year.
Experiments in Cambodia were designed to include: variety evaluation with respect to matching phenology to sowing opportunities; nutrition and legume nitrogen fixation; weed management and possibly tillage to minimise soil water loss during seedbed preparation. A comparative analysis report/workshop in conjunction with extension collaborators was also carried out in both countries in each of the four years.
In Australia, impediments to diversification and constraints to farm decision making were identified. Whole-farm models were utilised and farm case studies were prepared for situations where crop diversification had been successful in each region. The focus crops in Australia were chickpea, faba bean and canola. Tools were developed for climate risk analysis of alternative crop sequences. No field experimentation was conducted in Australia, but related field experimentation was undertaken in companion projects or in ongoing work by NSW Agriculture. In both countries the project was fully integrated within existing extension programs.

In Cambodia, a total of 153 on-farm experiments and demonstrations were conducted between 2004 and 2006. The experiments included: variety evaluation (43); insect pests and disease (19); reduced tillage (22); agronomy and farming systems (69). This work has impacted significantly on the CARDI approach to research in the uplands.
A significant response to inoculation of rhizobium on legumes was identified during the project research, and rhizobium inoculation techniques have been demonstrated to advisers in Cambodia. A rapid soil nitrate test has also been demonstrated to advisers and tested on 100 on-farm sites in Cambodia.
The project produced Field Guides for insect pest and weed identification in upland crops as well as Field Crop Manuals for soybean and maize in Cambodia. A 60-page book was also produced on gross margin analyses, and general marketing information is being prepared for the six focus crops in Cambodia. This information could potentially impact on the economic improvement of on-farm profitability, leading to poverty reduction.
An evaluation of the barriers to the adoption of no-tillage and conservation farming practices in Australia conducted by the NSW DPI showed that in 2000-2001, 24% of landholders surveyed reported no cultivation except at sowing (no tillage), 47% cultivated once or twice before sowing (minimum tillage) and 29% fell into the 'other' category, implying three or more cultivations (conventional tillage). Although there has been a shift towards no-till, the question was asked: "Why are almost 30% on average still using 'conventional' tillage?"
A series of 18 focus group meetings (involving 100 farmers and 20 agribusiness representatives) was conducted in NW NSW in 2005 to identify the barriers to the adoption of no-tillage and conservation farming practices. This culminated in a national conference attended by 130 people and publication of a book of 12 case studies on no-till conversions.
Improved practices identified in this project will be further developed in a follow-up project.